Effects of Different Land Use Change on Soil Aggregate and Aggregate Associated Organic Carbon: A Meta-Analysis

Soil aggregate functions in maintaining soil structure and protecting soil organic carbon (SOC).To illustrate the influence of land use change on soil aggregate total SOC and aggregate-associated SOC, we conducted a meta-analysis using data from published journals.Overall, land use changes significantly improved soil macro-aggregate and total SOC by 7.3% and 19.8%, respectively, compared with the primary land use type.The WSA 0.25 tended to increase by 63.8% and 37.9% in forest and grassland, respectively, while it decreased by 21.9% and 11.2% in farmland and garden, compared to primary land use.The change from ecological land to agricultural land significantly decreased WSA 0.25 by an average of 24.3%, but agricultural land change to ecological land increased WSA 0.25 by 49.2%.Soil clay, SOC, bulk density, and pH were the most important factors in explaining the variance in macro-aggregate content.The SOC content increased by 44.1% and 74.4% in forest and grassland, respectively, while it decreased by 16.2% in farmland.Changing agricultural land to ecological land increased the SOC and macro-aggregate associated SOC by 52.6% and 50.0%, respectively, and a positive correction was observed between macro-aggregate associated SOC and the content of WSA 0.25 rather than MSA 0.25 .Our meta-analysis provided a scientific basis to enhance soil structural stability and increase SOC storage.